Google's Core Web Vitals measure how fast a page appears, how quickly it responds and how stable it is. Here is what each one means for your customers.
Core Web Vitals are Google's set of user-experience metrics. They matter for search, but they matter more for people: a slow, jumpy page loses visitors before your message is read.
Largest Contentful Paint: does it appear quickly?
LCP measures when the main content of the page becomes visible. Google's guidance treats 2.5 seconds or less as good. Heavy hero images, render-blocking scripts and slow hosting are the usual causes of a poor score.
Interaction to Next Paint: does it respond?
INP measures how quickly the page reacts when someone taps, clicks or types. Google's “good” threshold is 200 milliseconds or less. Too much JavaScript running at once is the most common problem, especially from stacked plugins and third-party tags.
Cumulative Layout Shift: does it stay still?
CLS measures unexpected movement as the page loads: the button that jumps just as you go to press it. A score of 0.1 or less is considered good. Reserving space for images, embeds and banners fixes most issues.
What to do about it
- Serve correctly sized, modern-format images
- Load non-essential scripts after the page is usable
- Audit plugins and third-party tags regularly
- Reserve space for media and dynamic content
- Measure with real-user data, not only lab tests
